WordPress SEO was updated to version 1.5.5.1, from version 1.5.5. Changelog:

• Fixed a potential error with $canonical not being a sting after being filtered.
• Fixed more bugs with first paragraph keyword detection.
• Fixed bug in saving new opengraph title and images variables in the social settings.
• Fixed bug where SEO score incorrectly reported as ‘Bad’ when no focus keyword set, props smerriman for finding.
• Override woo_title() output harder than before to remove need for force rewrite with WooThemes themes.
• Replace %%parent_title%% variable client side through JS.
• updated ar, cs_CZ, fr_FR, hr, pl_PL, pt_BR and ru_RU
• new .pot file based off of the 1.5.5 version